This invention relates to disc brakes and in particular to so-called wedge operated disc brakes which comprise interleaved rotatable and non-rotatable brake discs within a brake housing, a ball and ramp type brake actuator comprising first and second relatively rotatable annular actuator discs with actuator balls therebetween located in circumferentially ramped pockets formed in opposing faces of the actuator discs, a wedge-shaped actuator member and an actuating means to displace the actuator member between confronting abutments on the respective actuator discs to relatively rotate the discs to cause the balls to rise up the ramped pockets and hence expand the actuator axially to move the brake discs into engagement.
Such wedge operated disc brakes are well known and are used, for example, in agricultural or industrial tractors and other similar vehicles.
Since such brakes are used in heavy braking applications it is a requirement to provide for the cooling of such brakes to avoid overheating.